It helps to first understand what your primary objective is…namely, to survive long enough to escape. Sometimes that point is so obvious, it gets overlooked. In a real street encounter, your objective is NOT to “win”, or otherwise defeat the attacker. It is to render him unable to harm you long enough that you can affect a safe escape.
Running TOO early may get you chased, or even shot in the back. Sticking around to win the fight may likewise get you hurt or killed, especially if he has friends and/or pulls a previously concealed weapon.
With your highest priority clearly in mind, you can now begin evaluating tactics in a useful way. While it is true that many fights, perhaps even a majority, can eventually end up either on the ground or at knee level, it’s worth noting that that same likelihood does NOT always apply to self-defense scenarios. The latter usually begin with the attacker having the advantage both of surprise and of unprotected targets. If the attacker knows the victim, the assault may turn into a fight. However, in cases of anonymous assault, the victim is more typically incapacitated, possibly killed with a weapon, and robbed. It is less likely in such situations for the attacker to go to the ground in a “fight” with the victim, since most attackers prefer to keep every advantage they can, including the advantage of staying upright while the victim is knocked down in order to facilitate a quick escape.
From the defender’s point of view, any chance to quickly stun or incapacitate the attacker and then run away should be a higher priority than engaging the attacker in a ground fight. Going to ground is always a gamble. Namely, (1) that you are more skilled in groundfighting than your opponent, (2) that he is unarmed or will be unable to present any concealed weapon, (3) that other attackers will not present themselves, AND (4) that the fighting surface will be relatively safe to land on and will contain no impromptu environmental weapons that an attacker may use against you. Further, it is also a gamble that, if any of the above mentioned problems do arise, you will be able to extricate yourself and escape in time, unharmed. This last gamble may be the biggest of all.
The information thus far would seem to favor prioritizing simple but reliable and devastating strikes over ANY type of grappling, whether upright or on the ground. However, reality often dictates that, as the potential victim, you often don’t get a choice of conditions in a real street attack. Therefore, having at least a reliable working knowledge of the basics of grappling and anti-grappling, both upright and on the ground, may be essential to your survival in a real street encounter. Even if ground grappling is not your forte, becoming familiar enough with it that you can escape from ground and get up to run away may mean the difference between life and death.
Personally, I believe Tony Blauer summed it up quite well in stating, “strike when you can, grapple when you have to”.